One hundred years ago next week, 2 April 1912, the largest moving man-made object on Earth eased into Belfast lough and set off for Southampton, Cherbourg, Queenstown and, eventually, New York City. For three years, Belfast had watched the RMS Titanic's enormous hull come together, rivet by rivet, in the Harland and Wolff dockyards, and its launch in May 1911 had been a big day for the city: thousands of ticket-holding spectators were joined by a clutch of dignitaries and more than 100 members of the press.

In 1912, thirteen days after leaving Belfast fully fitted, the Titanic lay at the bottom of the Atlantic, and 1,517 people were dead. "It was such a shock for people [in Belfast]," says Susie Millar, whose great-grandfather was on board, and drowned. "They felt that their pride had been dented. They felt perhaps they were being punished for having that pride in the first place."

For two generations, she says, the city felt "a sense of shame and of embarrassment, and instead of dealing with it, in true Northern Ireland style we swept it under the carpet".

If Belfast was once ashamed of its connection with the Titanic, it is fair to say it has got over it. Next week will see the launch of the Titanic Belfast festival, "a fusion of international-scale events" to mark the centenary of what was once merely a terrible tragedy, but has become a source of pride to the city – and potentially a very lucrative cash cow.

At least seven different plays related to the sinking are being staged in the city, alongside Titanic: The Musical at the city's Grand Opera House. Two separate choral works have been commissioned, and a memorial garden will be unveiled at the City Hall.

The slipways from which the ship was launched will host an interactive light show and an MTV pop concert, and serve as the start of a new stage of the Circuit of Ireland motor rally.

Locals can host on-board Titanic-themed hen nights on Belfast lough, take tours on Titanic-liveried buses around the city or even tuck into the Titanic-themed crisps on sale in local shops – "All aboard: only 60p".

Biggest and showiest of all, next week will also see the opening of Titanic Belfast, an enormous £100m visitor attraction built on the slipway itself, which its cheerleaders hope will do for the city what the Guggenheim did for Bilbao – and what the film-maker James Cameron did for the marketability of what was once seen principally as a terrible tragedy.

It's not hard to see where the money has been spent. Using original photographs and video, CGI animation, 3D imagery, recreated cabins and a ride in suspended carts, Titanic Belfast's nine galleries tell the story of the ship's construction in what was then the busiest shipyard in the world, its fit-out, launch, its catastrophic end – and its second life as possibly the most famous ship that ever sailed.

The building in which it was housed is no less arresting: a sparkling behemoth that consciously evokes the White Star Line logo, the ship itself and, perhaps oddly, the iceberg that proved its comeuppance. "I'm looking forward to hearing the nicknames Belfast gives it," says its lead architect, Angus Waddington.

The building towers above the now ramshackle Edwardian drawing offices in which the Titanic and its sister ships were designed, but ambitions for Titanic Belfast are even higher. It's flattering, says Waddington, if people compare the building to the Guggenheim: "I think people want to mention that simply because it was such a catalyst for Bilbao and it was seen as a turning point in its reinvention, a shipbuilding, industrial city getting a new lease of life."

Tim Husbands, Titanic Belfast's chief executive, is equally bullish, describing the attraction as "a product that could transform the face of tourism in Northern Ireland. I don't say that without evidence. We have been marketing it for the past nine months or so and we already have some 80,000 tickets sold. The new emerging markets of China, India and Australia are showing significant interest in us as a product, and Northern Ireland has never had that – in fact Ireland doesn't have a tourism product that is marketed in that way." The centre's estimates predict a £24m boost to the local economy in 2012 alone.

Others, however, are considerably more sceptical. In a downbeat assessment in December, the Northern Ireland Audit Office (NIAO) expressed concerns that the attraction could struggle to attract the 290,000 visitors it needs each year just to break even. "If predicted visitor numbers do not materialise," it found, "the long-term future of the building would be doubtful." At least £60m of public money had been spent on Titanic Belfast, noted the NIAO; its total spend meant that "compared to other world-class attractions, the Titanic Signature Building will be one of the most expensive relative to the number of visitors it expects to attract".

Husbands, whose team describe Titanic as the second-biggest brand in the world after Coca-Cola, is unwavering, however. "There are Titanic visitor attractions all over the world doing very good business with absolutely no link at all to Titanic. We have a very authentic story to tell, and that's why we're very confident that we will have longevity." It will rely not only on visitor revenue. The top floors of the building – and its best views – are given over to a conference and banqueting centre. It is here that organisers have situated a painstaking replica of Titanic's sweeping staircase, lent particular fame by Cameron's 1997 blockbuster. Ordinary visitors paying the £13.50 entrance fee won't get to see it. In the narrow, redbrick terrace streets of Protestant east Belfast, from which many shipyard workers – 15,000 of them in 1912 – were drawn, the shiny new building just down the road in what is now termed Belfast's "Titanic Quarter" is seen as an almost distant curiosity.

John Keenan has a few commemorative teapots in the window of his "Union Jack Shop", but "we've always done that. I'm selling a few more than usual, but there's not that much money about."

Despite living in the shadow of Harland and Wolff's famous yellow cranes – "you can't open your eyes in the morning but you see the cranes" – he says local people have been "badly left behind" by the Titanic commemorations. "Obviously in this part of Belfast, if you go back into your family history there's someone who worked in the shipyards back then. But all the pensioners who live on this road, they are not going to trek over to see a Titanic museum. The tourist buses go about here, they slow down at the murals, click click click click click, but they don't stop. So how is it helping east Belfast?" For Susie Millar, however, who will spend the centenary on board a ship at the north Atlantic wreck site, the renewed global interest in Titanic, and in Belfast's part in its story, is only to be welcomed.

"We've a lot to thank the diving team who found the wreck, along with James [Cameron], Kate [Winslet] and Leonardo [DiCaprio]. They helped us recognise what an appetite there was out there in the world for Titanic stories. That's when we started to think: 'Hang on a minute, we have a great story to tell here in Belfast.'"

• This article was amended on 27 and 28 March 2012. The original said that RSS Titanic eased into Belfast lough and set off for New York City, and also implied that she sank thirteen days after her launch. This has been clarified.